THOUSAND OAKS, Calif. (AP) — John Sullivan got his usual day off to rest Wednesday, a reminder of just how important the center has been in his first season with the Los Angeles Rams.

When the Rams play at the Minnesota Vikings on Sunday in Sullivan's return to the city where he spent the first seven years of his career, that value will be on display against one of the NFL's best defenses.

"They don't give up cheap things," Rams coach Sean McVay said. "Every yard that you get is earned, and it's hard-earned yards."

The Rams' offensive renaissance will be tested by a unit that ranks second in the league allowing 4.7 yards per play. The Vikings are allowing 18.3 points per game, which is tied for fifth best, and have held seven opponents under 20 points.

McVay's respect for Vikings coach Mike Zimmer was evident as he discussed how Minnesota can get to the quarterback with or without blitzing.

"The thing that's so challenging about them is they can hit home with a four-man rush and play loaded zone behind it or they can give you a bunch of different issues with some of their fire zones and different pressures that they present in a lot of those known passing situations," McVay said.

McVay will trust in Sullivan's ability to diagnose the defense to help quarterback Jared Goff and the rest of the offensive line.

Now in his ninth season, Sullivan has been critical as the Rams have allowed just 13 sacks through nine games.

The first-year coach said Sullivan, who signed a one-year contract with the Rams in April, is as sound a football mind as he has been around, including players and coaches.

"He sees how everything fits and goes together," McVay said. "It's almost like sometimes defensively it's a puzzle. If this guy is here, well this is what's got to occur, and he's got a very intricate understanding of that. When you talk football, it doesn't really take long to figure that out."

Right tackle Rob Havenstein also said Sullivan's intelligence is his best attribute, but then cautioned not to overlook his ability to communicate what he sees on the field to the rest of the offense or how he still has the physical tools to deal with big interior defenders.

All of those traits will be challenged, especially if the Vikings are without top defensive end Everson Griffen, who has 10 of the team's 25 sacks. If Griffen misses his second straight game with a foot injury, Zimmer could call more blitzes to generate the pass rush lost because of his absence.

No matter the circumstances, the Rams trust Sullivan will keep the offense on track.

"We always talk about (offensive tackle Andrew) Whitworth a lot with what he's done, especially on the left side, but John has been tremendous in his own way," Goff said.

"For him to make all those calls and just be so in tune every game with every look and every little thing, it's so good and he's been tremendous this year and a great help for myself and a big reason why our offense has been so successful."

NOTES: Left guard Rodger Saffold (ankle) and safety Lamarcus Joyner (hip) did not practice. Outside linebacker Robert Quinn (illness) was limited.

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